Economic analysis of dengue prevention and case management in the Maldives.

As tourism is the mainstay of the Maldives' economy, this country recognizes the importance of controlling mosquito-borne diseases in an environmentally responsible manner. This study sought to estimate the economic costs of dengue in this Small Island Developing State of 417,492 residents. The authors reviewed relevant available documents on dengue epidemiology and conducted site visits and interviews with public health offices, health centers, referral hospitals, health insurers, and drug distribution organizations. An average of 1,543 symptomatic dengue cases was reported annually from 2011 through 2016. Intensive waste and water management on a resort island cost $1.60 per occupied room night. Local vector control programs on inhabited islands cost$35.93 for waste collection and $7.89 for household visits by community health workers per person per year. Ambulatory care for a dengue episode cost$49.87 at a health center, while inpatient episodes averaged $127.74 at a health center,$1,164.78 at a regional hospital, and $1,655.50 at a tertiary referral hospital. Overall, the cost of dengue illness in the Maldives in 2015 was$2,495,747 (0.06% of gross national income, GNI, or $6.10 per resident) plus$1,338,141 (0.03% of GNI or $3.27 per resident) for dengue surveillance. With tourism generating annual income of$898 and tax revenues of $119 per resident, results of an international analysis suggest that the risk of dengue lowers the country's gross annual income by$110 per resident (95% confidence interval $50 to$160) and its annual tax receipts by $14 per resident (95$7 to $22). Many innovative vector control efforts are affordable and could decrease future costs of dengue illness in the Maldives

The burden of dengue and force of infection among children in Kerala, India; seroprevalence estimates from Government of Kerala-WHO Dengue studyResearch in context

Summary: Background: Dengue shows high geographic heterogeneity within and across endemic countries. In the context of increasing burden and predicted outbreaks due to climate change, understanding the heterogeneity will enable us to develop region specific targeted interventions, including vaccination. World Health Organisation (WHO) suggests standard methodologies to study the burden and heterogeneity at national and subnational levels. Regional studies with robust and standard methodology to capture heterogeneity are scarce. We estimated the seroprevalence of dengue in children aged 9–12 years and the force of infection in Kerala, India, from where Zika cases also have been reported recently. Methods: We conducted a school-based cross-sectional survey in 38 clusters; selected by stratified random sampling, representing rural, urban, high burden and low-burden administrative units. Validation of Indirect IgG ELISA was done by Plaque Reduction Neutralization Test (PRNT90) using the local isolates of all four serotypes. Force of infection (FOI) was estimated using the WHO-FOI calculator. We conducted a follow-up survey among a subsample of seronegative children, to estimate the rate of sero-conversion. Results: Among 5236 children tested, 1521 were positive for anti-dengue IgG antibody. The overall seroprevalence in the state was 29% (95% CI 24.1–33.9). The validity corrected seroprevalence was 30.9% in the overall sample, 46.9% in Thiruvananthapuram, 26.9% in Kozhikkode and 24.9% in Kollam. Age-specific seroprevalence increased with age; 25.7% at 9 years, 29.5% at 10 years, 30.9% at 11 years and 33.9% at 12 years. Seroprevalence varied widely across clusters (16.1%–71.4%). The estimated force of infection was 3.3/100 person-years and the seroconversion rate was 4.8/100 person-years. 90% of children who tested positive were not aware of dengue infection. All the four serotypes were identified in PRNT and 40% of positive samples had antibodies against multiple serotypes. Interpretation: The study validates the WHO methodology for dengue serosurveys and confirms its feasibility in a community setting. The overall seroprevalence in the 9–12 year age group is low to moderate in Kerala; there are regional variations; high burden and low burden clusters co-exist in the same districts. The actual burden of dengue exceeds the reported numbers. Heterogeneity in prevalence, the high proportion of inapparent dengue and the hyperendemic situation suggest the need for region-specific and targeted interventions, including vaccination. Funding: World Health Organization